Objective To compare the clinical results of minimally invasive percutancous plate os-teosynthesis (MIPPO) and open reduction with internal fixation (ORIF) for treatment of distal tibial fractures. Methods From October 2006 to June 2007, 94 cases of closed distal tibial fracture with intact articular surface were treated by internal fixation with plates. Of them, 42 were treated with ORIF and 52 with MIPPO. We retrospectively analyzed their union time, malunion and complications. Results The average follow-up was 14.5 (8 to 24) months. In the ORIF group, 35 cases got union, 3 cases delayed union and 4 cases nonunion. The average time for union was 3.83 (3 to 8) months. There were no cases of malunion and 2 cases of superficial infection in this group. In the MIPPO group, 47 cases obtained union, 5 cases delayed union and none nonunion. The average time for union was 3.66(2 to 8) months. No significant differences were found between the 2 groups in total union time or in the union time for Type AI, Type A2 and Type B fractures respectively. The union time for Type A3 fracture was longer in the MIPPO group than in the ORIF group, but the union time for Type C fracture in the MIPPO group was shorter than in the ORIF group. In the MIPPO group, external rotation occurred in 2 cases and posterior angnlation displacement in 3, and 8 cases com-plained of discomfort around the ankle which was relieved after removal of the plate. Conclusions Gen-erally speaking, there is no significant difference between ORIF and MIPPO in union time for distal tibial fractures. ORIF may be superior to MIPPO in treatment of Type A3 fracture, but inferior to MIPPO in treatment of Type C fracture. A high rate of delayed union may be expected in patients who have been treated with MIPPO and have had anteroposterior angnlation.

Objective To explore and evaluate the efficacy and safety of mechanical thrombectomy with the Solitaire AB Revascularization Device in acute basilar artery occlusion.Methods Nine patients with basilar artery occlusion were treated with direct thrombectomy by using Solitaire AB stent retrievers between August 2010 and October 2012.Stent angioplasty was performed for patients with serious residual stenosis.Neurologic status was evaluated before and after treatment according to the National Institutes of Health Stroke Scale (NIHSS) and modified Rankin scales (mRs).Neurologic status was evaluated after treatment according to the NIHSS and mRs 6 months after stent placement.Stent patency at follow-up was assessed by MR angiography,or DSA 6 months after stent placement.Results Successful revascularization was achieved in all patients.Stenting and angioplasty were performed in 6 patients with serious residual stenosis.The complication of cerebral hemorrhage did not occur in any patient.Acute thrombosis happened in one patient one day after procedure.Emergent angiography showed re-occlusion of basilar artery.Intraarterial thrombolytic therapy was given,and reperfusion was achieved,but the patient died 6 days later.One patient developed coma at 4th month of follow-up.MRA showed acute basilar artery occlusion again and magnetic resonance imaging showed extensive ischemic damage of the brainstem.The patient died during the conservative treatment period.The mean NIHSS scores were 2.4 ± 1.2 at discharge.The mRs scores were 0 in 2 patients,1 in 4 patients,2 in one patient,and 3 in 1 patient at discharge.Conclusion Mechanical thrombectomy with the Solitaire AB stent in acute basilar artery occlusion is relatively safe and effective.

Objective To evaluate the safety and feasibility of Wingspan stent for patients with symptomatic M1 stenosis of middle cerebral artery (MCA). Methods Thirty-two cases with recurrent symptomatic MCA stenosis resistant to medical therapy treated by self-expanding stent were reviewed retrospectively [average (49±19) years old, 13 women]. All patients underwent angioplasty and stenting with the Gateway balloon-Wingspan stent system. After 6 months, all patients were followed up by telephone or clinic, and advised followed up with DSA or TCD. Results Thirty-two patients were successfully stented during the first treatment session. The mean degree of stenosis reduced from (76.5±15.4)% to (19.3±9.2)%. The number of complicating subarachnoid hemorrhage was one, and occlusion occurred on one patients related to balloon angioplasty. During a follow-up of 6 months, there was no recurrence of transient ischemic attack or stroke in 32 available patients. Cerebral hemodynamics using transcranial Doppler monitoring were normal in 19 follow-up patients. Six-month angiographic follow-up was obtained in 5 patients, demonstrating good patency in 5 stenting vessels. The other patients refused to perform TCD or DSA. Conclusions Wingspan stent for symptomatic stenosis of middle cerebral artery appears to be a safe and feasible under strict control of periperformeral project. However further study is needed to evaluate the long-term effect.

BACKGROUND:Patients with elder hip fracture has more complications, poor affordability and high perioperative risk, so the preoperative ful preparation and evaluation are needed.
OBJECTIVE:To predict the accuracy of the prognosis of elderly patients with hip fracture through comparing the difference between American Society of Anesthesiologists score and Daping orthopedics operation risk scoring system for senile patients.
METHODS:A retrospective study was performed on 300 cases with elderly hip fracture selected from January 2011 to December 2012 from Department of Orthopedics, Gongli Hospital of Pudong. American Society of Anesthesiology score and Daping orthopedics operation risk scoring system for senile patients were conducted before treatment, and the predictive values of two scoring systems on the incidence of complications and mortality were compared.
RESULTS AND CONCLUSION:According to the American Society of Anesthesiology score and Daping orthopedics operation risk scoring system for senile patients, 148 cases and 97 cases had complications respectively. On the contrary, the actual number of complications was 89. The former predicted value was significantly higher than the actual value, and there was no significant difference between the latter forecast value and the actual value. The numbers of death predicted by American Society of Anesthesiology score and Daping orthopedics operation risk scoring system for senile patients were 27 cases and six cases, but the actual number of death was three cases, indicating that former predicted value was significantly higher than the actual value, and there was no significant difference between the latter predicted value and the actual value. The American Society of Anesthesiology score has a certain errors in predicting the postoperative complications and mortality of patients with elderly hip fractures, but it is simple and useful in clinic. The Daping orthopedics operation risk scoring system for senile patients can accurately evaluate elderly hip fracture operation risk, and can predict the postoperative complications and mortality more objective when compared with the American Society of Anesthesiology score.

BACKGROUND:Repair programs of posterolateral tibial plateau fracture included posterior plate screws, lateral plate screw and anterior and posterior lag screw fixation. To choose which fixation methods depends on clinical experiences of physicians. Study results are mainly clinical reports, and lack of mechanical evidence.
OBJECTIVE:To compare biomechanical changes in three fixed manners (lateral plate screw group, posterior plate screw group and anterior and posterior lag screw group) in the repair of posterolateral fracture of tibial plateau from the angle of biomechanics.
METHODS:A total of tibial specimens of six adult male antisepsis corpses (12 samples) were used for measuring bone mineral density of metaphysis. 1/2 posterolateral tibial plateau fracture model was established by electric pendulum saw. The model was randomly divided into three groups:lateral plate screw group, posterior plate screw group and anterior and posterior lag screw group. Finite element method and biomechanics were used to test axial displacement value and the maximal displacement distribution area under the axial loads of 250, 500, and 1 000 N.
RESULTS AND CONCLUSION:There was no significant difference in average bone density in three groups of metaphysis (P>0.05). The minimum axial displacement of the fracture fragments was in the anterior and posterior lag screw group (0.013 521 mm), fol owed by posterior plate screw group (0.016 991 mm), and the maximum was visible in the lateral plate screw group (0.138 200 mm) under 250 N load. Displacement value was similar to the 250 N under 500 and 1 000 N. According to the results of biomechanics, displacement values of anterior and posterior lag screw was obviously less than the lateral plate screw group and posterior plate screw group (P<0.05). There was no significant difference between the lateral plate screw group and posterior plate screw group (P>0.05). The maximal displacement distribution area was proximal tibiofibular joint border zone in two methods. These data indicated that the biomechanical stability was most advantageous in the anterior and posterior lag screw group, and poorest in the lateral plate screw group. In the clinic, anterior and posterior lag screw fixation can be used as a first choice for repair of posterolateral tibial plateau fracture.

Objective:To investigate the changes of mean venous sinus pressure (MVP) and trans-stenosis pressure gradient in patients with idiopathic intracranial hypertension (IIH) under awake setting and general anesthesia.Methods:Thirty-eight patients with IIH accepted venous sinus stent implantation in our hospital from January 2010 to January 2020 were chosen in our study; their clinical data were analyzed retrospectively. The manometry results of these 38 patients were recorded under awake setting and general anesthesia before stenting; MVP and trans-stenosis pressure gradient were obtained and compared.Results:MVP in the superior sagittal sinus, torcular, transverse sinus and sigmoid sinus showed no significant difference between patients under awake setting and general anesthesia ( P>0.05). Mean trans-stenosis pressure gradient in patients under awake setting ([22.784±7.606] mmHg) was significantly higher as compared with that in patients under general anesthesia ([18.388±8.992] mmHg, P<0.05). Conclusion:Mean trans-stenosis pressure gradient in patients under awake setting is higher as compared with that in patients under general anesthesia, and selection for venous sinus stent implantation should be decided by trans-stenosis pressure gradient in patients under awake setting.

BACKGROUND:Satisfactory clinical results have been achieved in the treatment of Sanders Ⅲ calcaneal fractures by percutaneous compression fixation with three-dimensional frame screws.However,whether the stability of minimally invasive plate internal fixation can be achieved in terms of biomechanics,and the advantages and disadvantages after comparison are still unknown. OBJECTIVE:To investigate the fixation effect of different internal fixation devices on Sanders Ⅲ calcaneal fractures by finite element analysis. METHODS:A finite element model of Sanders Ⅲ calcaneal fracture was made based on CT data of a 26-year-old healthy male volunteer.The calcaneal fracture models were fixed by minimally invasive three-dimensional frame screws and minimally invasive Y-plate.The longitudinal loads of 350 and 700 N were applied respectively.The displacement and stress distribution of the two models were analyzed,and the stability of each model was compared. RESULTS AND CONCLUSION:(1)The peak stress of bone block and implant in the minimally invasive three-dimensional frame screw model was significantly lower than that in the minimally invasive minimally invasive plate model.The average stress of bone block and implant in the three-dimensional frame screw model was also significantly lower than that in the minimally invasive plate model.(2)The maximum displacement of the two models was located at the medial side of the articular surface of the posterior talus,and the maximum displacement of the three-dimensional frame screw model was smaller than that of the minimally invasive plate model.(3)The longitudinal displacement between the anterior fragment and the medial fragment of the minimally invasive plate model was smaller,and the transverse and vertical displacement between the medial fragment and the middle fragment of the three-dimensional group screw model was smaller.(4)It is concluded that both of the two internal fixation models can provide satisfactory fixation effect.The three-dimensional frame screw model can provide better transverse and vertical stability with more uniform stress distribution and smaller comprehensive displacement of bone fragments,while the minimally invasive plate has more advantages in maintaining longitudinal stability.

Objective To investigate the effect of medial collateral ligament (MCL) repair and coronoid process fracture fixation on stability of the Terrible Triad of the elbow. Methods CT and MRI scan images of elbow joints from one healthy 28-year-old male volunteer were used to establish three elbow models. Model A: normal model. Model B: repair of coronoid process fractures, without MCL repair. Model C: repair of MCL, without repair of ulnar coronoid processes. Longitudinal loads were applied on the three models to analyze the displacement and stress distributions of the elbow joint under different working conditions and compare the stability of the elbow joint. Results The displacement and stress distributions of the three models were similar. The maximum displacement and maximum stress of the articular surface were located at the ulna pulley notch, while the minimum displacement was located at the coronoid process and its medial side. The minimum stress was located at the lower lateral side of the coronoid process. There were no statistical differences in the maximum displacement and stress among the three models (P>0.05). Conclusions When the lateral column is stable, the effect of repairing the MCL and fixing the fracture block of ulnar coronoid process is similar.